Mh/full pipeline diffusion adjusted scores

[moritzhauschulz]

Description

This PR basically does two things:

1. It fixes the SSR computation. Previously, the member RMSE was used as denominator. I (and Claude) think this should be ensemble RMSE.
2. It fixes some dead-end ('return None') in score.py

This should probably be reviewed by someone from the eval team (maybe @iluise ?).

With this fix, and the fix in the eval config, I can now produce CRPS, SSR and spread plots and maps (pretty much out of the box).

Issue Number

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Checklist before asking for review

• I have performed a self-review of my code
• [] My changes comply with basic sanity checks:
  • I have fixed formatting issues with ./scripts/actions.sh lint
  • I have run unit tests with ./scripts/actions.sh unit-test
  • I have documented my code and I have updated the docstrings.
  • I have added unit tests, if relevant
• I have tried my changes with data and code:
  • I have run the integration tests with ./scripts/actions.sh integration-test
  • (bigger changes) I have run a full training and I have written in the comment the run_id(s): launch-slurm.py --time 60
  • (bigger changes and experiments) I have shared a hegdedoc in the github issue with all the configurations and runs for this experiments
• I have informed and aligned with people impacted by my change:
  • for config changes: the MatterMost channels and/or a design doc
  • for changes of dependencies: the MatterMost software development channel

[clessig]

@moritzhauschulz : can we also open this against develop please.